Betta with some guppies

It will mostly depend on the betta. Some will go after male guppies because of their big tails. The guppies might try to nip on the betta as well.
 
I have one male betta in with 4 guppies, 3 female, 1 male. At first he went after them, but after about 15 mins he stopped and now they are all getting along fine. I am moving the betta soon though because I want the fry to survive this time.
 
i tried it

IMO,
i wouldn't risk it. guppies or any fish with large colorful plummage can trigger some betas to attack. but like others say, it all depends on your beta. i put my beta, which i had for 5 years, into a community tank with sailfin mollies and guppies and it literally flared up and attacked them to a point where i had to take him out. it might work, i just wouldnt risk it
 
I think it also boils down to the size of the tank. I had a betta in a 29 with my guppies and they never had any problems. He would bully them around but that is about it. HE would prove to every one that he owned that tank and he did. That was about it. No serious attacks or anything like that.
 
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